劉格非2006-07-252018-07-092006-07-252018-07-092000http://ntur.lib.ntu.edu.tw//handle/246246/2742本研究的重點在於發展波譜元素 法，此方法同時包含快速計算與可求得空 間中任一點的優點。本方法的基礎建立於 波譜法與有限元素的原理，其為權重餘數 法（MWR）的一種。波譜法為一整體近似 （global apporximation），其重點在於 選取一適合的基函數。在本研究中所選取 的基函數為Chebyshev 多項式，其優點在 於可處理非週期性的邊界問題。並在研究 中利用有限元素的概念將問題的定義域 （domain）分割成數個次定義域（subdomains）， 以加快計算的收斂速度及增加計算時的精度。 經應用後，證實此方法具有快速收斂與不 需非常大的mode 數即可得高精度的優 點。但當增加元素與mode 的數目時，矩 陣數目亦會成倍數增加。所以次定義域的 數目需就問題的定義域來決定出最佳的 數目，並且根據所要求精度決定mode 的 數目，以免矩陣過於龐大。The purpose of this research is to develop the Spectral Element Method. The trial functions that we chose is Chebyshev function, and it can deal with non-period boundary problem. And we use the concept of the Finite Element Method to divide computational domain to several subdomains. It can speed up the convergence rate and the accuracy . It can be seen from application that this method converges very fast and gets high accurate. The numbers of modes and subdomains must be chooser so as to achieve the maximum computational effeciency. The development of slope land in Taiwan is rapidly growing, so is the potential hazard for debris flow. Therefore, identification of these potential hazard area will be an important task. The flowbility of debris flow is a control factor in estimating the size of these area. This study develops a numerical model utilizing nonlinear constitutive law and fluid conservation laws. Model can be used in field and the values of all parameters used in the model will be obtained through simple in situ tests.application/pdf54277 bytesapplication/pdfzh-TW國立臺灣大學土木工程學系暨研究所波譜元素法數值模擬Finite element spectral methodNumerical simulationreporthttp://ntur.lib.ntu.edu.tw/bitstream/246246/2742/1/892213E002074.pdf